Bobbin holder



March 28, 1961 J. F. KING, JR 2,977,067

BOBBIN HOLDER Filed March 26, 1957 3 INVENTOR 4 James E Ki J" fm dfiew & l m w ATTORNEY 2,911,11 .1 BOBBIN HOLDER James'F. King, "In, Winston-Salem, N.C-., assignor to The hahnson Company, Winston-Salem, N.C.,'a corporation of North Carolina Filed .Mar. 26, 1957, Ser. No. 648,653 7 2 Claims. or. 241-1301 This invention relates; m bobbin holders for use on textile processing machines and in particular to bobbin holders of the suspension type comprising a pair of spring loaded jaws which are maintained relatively close to each other in opposition to the spring force as they enter the longitudinal bore of the bobbin by upward movement of the latter, the jaws including shoulders at their lower end portions which, upon entry into a larger diametered section of the bore, expand into engagement with a complementary shoulder formed at the junction of the larger and smaller diametered bore sections and thus secure the bobbin to the holder.

Various constructions for bobbin holders of the suspension, spring jaw type have been knownforsome time. However, prior to. the present improved construction to be hereinafter described in detail and defined in the appended claims, it has been the practice to make the jaws from a single length of material bent into a generally inverted U-shape and to rely upon the inherent resiliency in the jaws to expand the shouldered portions of the same outwardly against the complementary shouldered portion in the bobbin bore. The disadvantage of this construction is that after the bobbin holder has been in use for some time and subjected to hundreds of flexing cycles as bobbins are installed and removed, the metal from which the U-shaped holder is made becomes fatigued and either breaks or loses so much of its essential inherent springiness that it is no longer able to hold the bobbin in place. Another disadvantage of this type of bobbin holder is that the spring force of the jaws is generally constant and hence different holders with 'difierent degrees of spring force are necessary in order to support different sizes and Weights of bobbins that are generally used in a textile mill.

It is accordingly a primary object of this invention to provide an improved construction for a bobbin holder which will resist fatigue thus resulting in a longer useful life of the holder. Another primary object of the invention is to provide an improved bobbin holder in which the spring force tending to move the jaws apart adjusts itself automatically as a function of the distance between the jaws, the force increasing as the jaws move farther apart thereby providing the necessary stronger holding force for the larger and heavier bobbins which in general are provided with a larger diametered bore and a desirably lesser holding force for the smaller and lighter bobbins which-in general are provided with a smaller diametered bore. i

In particular, the improved holder construction features two structurally separate and relatively rigid jaw members arranged in confronting relation, the lower portions of the jaw members being provided with shoulders to engage complementary shoulders in the bore of the bobbin and the upper portions of the jaws being connected together by means of a hinge assembly so as to enable the jaws to execute the necessary movement towards and away from each other as they are entered ,into or pulled out from the'bobbin bore. A spring unit interposed beice tween the jaws servesto urge the. jaws away from each other and the construction of the spring is such that its .force increases'als the distance between the jaws increases thus providing a variable spring force which adapts the holder to use bothfor larger and smaller bobbins. In particular, the spring comprises a multi-turn helically coiled section located between the jaws and two rather long arms extending from opposite ends of the coiled section which press outward respectively 'against the inner faces of the jaws. The multi-turn coiled section of'the spring makesit better resistant to fatigue and the rather long arms extending therefrom establish the desirable outwardly increasing pressure as the jaws are forced open.

Thus, when the jaws become only slightly separated when supporting a comparatively small and light bobbin such as for example an 8 x 4, the jaw pressurevwill be correspondingly light, and when the jaws become further separatedwhen supporting a comparatively large and heavy bobbin such as for example a 12 x 7 /2, the jaw pressure will be correspondingly increased because of the greater separation of the jaws. This automatically compensating difference in holding pressure is not only de sirable in view of the difference in mass to be suspended but also substantially equalizes the pull off force required to remove the empty bobbins from the holders regardless of size.

Still another feature of the improved construction resides in'the .use of a washer or collar surrounding the 'hingedly connected jaws and a helical spring also surrounding the jaws above the collar. The collar is free to ride up and down the jaws as the latter are brought together or spread apart and the function of the collar is two fold. 'One such function, when the collar occupies its lowermost position, is to hold the jaws together after they reach such a position upon removal of an empty bobbin thus facilitating placement of a full bobbin. The other function, when the collar occupies its uppermost position, is to limit separation of the jaws. The function of the spring which is maintained in compression against the collar is to make certain that the collar will follow down the jaws as the latter are moved closer to each other and thus lock the jaws together until the collar is again moved upward along the jaws by contact with the end face of a bobbin as the latter is pushed onto the jaws. 1

Still another advantage residing in the improved bobbin holder in accordance with the invention is that the suspension type support for the holder, which must be able to rotate about its longitudinal axis as the textile strand is pulled off the bobbin as it is processed on the machine, incorporates a novel type of braking or damping system which controls rotation of the bobbin and its holder in such manner that a substantially uniform tension or drag is maintained on the bobbin. In'particular, the improved braking system is incorporated in the suspension bearing assembly, the latter including a bearing pin which passes through an opening in a washer made of Teflon, the

'pin including a rounded head which rests upon the marginal portions of the washer opening so as to suspend the pin and the jaws secured to the latter in such manner that the pin is free to rotate on its Teflon support washer and simultaneously oscillate about the pin axis. A damper vane is secured to the head of the bearing pin and extends transversely of the same and the vane rotates with the pin in a chamber filled with a grease. Passage of the vane through the grease creates a resistance or drag which results in the application of a constant drag or braking force on the holder and bobbin carried by it.

The amount of braking force can, of jcourse, be varied as The foregoing as well as other objects and advantages inherent in the invention will become more apparent from the following detailed description of a preferred embodiment thereof and from the accompanying draw: ings in which: Fig. l is a view in elevation of the improved bobbin holder, the view also showing the manner in which the holder is attached to a creel rail and a bobbin in position ready to be fitted to the holder;

Fig. 2 is a view similar to Fig. 1 but in central vertical section;-

Fig. 3 is a view similar to Fig. l but showing the bobbin in place on the holder and with the shouldered portions of the jaws of the holder engaged with a complementary shouldered portion in the bobbin bore;

Fig. .4 is a transverse section taken on line 44 of Fig. 2.

Fig.' is a transverse section taken on line 55 of Fig. 2;

Fig. 6 is an end view of one of the two jaws of the bobbin holder; 7

Fig. 7 is a fragmentary view in elevation showing the inside of one of the jaws and the expander spring; and

Fig. 8 is a transverse section on line 8-8 of Fig. 1 through the creel rail and showing a portion of the retaining cap and attachment nut in elevation.

With reference now to the drawings, the improved bobbin holder comprises a pair of jaws 1, 1' having the general configuration of a spoon arranged in depending confronting relation. The jaws are preferable made of steel and are relatively inflexible about their longitudinal axis. The lower portions of the jaws terminate in bowl portions 2, 2' which establish external shoulders 3, 3'. The shank portions 4, 4 of the jaws have a slight inward taper in the upward direction and the upper ends of the jaws terminate in a bifurcation establishing outwardly turned sets of tongues 5, 5 which pass through a correspondingly configured diametrally extending slot 6 in a washer 7. The junction of the tongues 6 with the washer 7 establishes a pivotal connection which permits the jaws 1, 1 to move towards and away from each other.

Embraced by the upper ends of the jaws 1, 1 is the lower end of a generally vertical bearing pin 8, the pin having a longitudinally extending portion 9 of reduced cross section embraced by the upper ends of the jaws to prevent the latter from being pulled off the pin. The pin 8 which is non-rotatable relative to the jaws 1, 1', passes through a central aperture 11 in a slightly conical bearing washer 12 preferably made out of Teflon. The upper end of pin 8 is enlarged to provide a bottom rounded head 13 which seats on the marginal portions of the central opening 11 in bearing Washer 12 to establish a suspension bearing for the bearing pin 8 and jaws, 1, 1 which permits the pin and jaws to rotate as a unit about their longitudinal axis and also permits the pin and jaws to move pivotally about the suspension point. For securing the bearing washer 12; in place, a cup shaped member 14 is utilized, the washer 12 being retained in a recess provided in the bottom of the cup member 14 by a retaining washer 15 which is press fitted into place. The bottom of the cup member 14 and the retaining washer 15 are provided with central apertures so as to pass the shank portion of the bearing pin. Moreover, the central aperture in the retaining washer 15 is enlarged sutficiently to permit the desired swivel movement of the bearing pin.

Extending transversely from opposite sides of the head portion 13- of the bearing pin 8 and secured thereto is a damper vane in the form of a short length of straight wire 16 which is located within the cup 14. The cup 14 together with the bearing pin 8 and jaw assembly is inserted into a cap 17 and retained in the latter by -means of a plurality of set screws 18. The rim of the cup 14 bears against the end wall of cap 17 and thus establishes a closed chamber within the cup 14 which is 4 filled with grease of a proper consistency to give the desired damping effect to rotation of the pin and jaw assembly as the wire is dragged through the grease. Rotation of the pin and jaw assembly is, of course, caused by the pull-oft of the textile strand or roving, etc. from the bobbin which is secured to the holder.

A threaded stud 21 integral with the cap 17 extends upwardly through a longitudinal slot 22 in the lower horizontal face 23 of a creel rail 24 which, in the present illustrated embodiment, is seen to be triangular in transverse section.

The stud 21 threads into an elongated nut 25 and the length of nut 25 is seen to be less than the width of the bottom face of the creel rail and hence establishes a stop for the nut 25 which permits the stud 21 to be screwed down until the surface of the cap 17 presses tightly against the lower face 23 of the rail 24. This arrangement is not only simple but enables one to locate the bobbin holder at any position along the length of the creel rail without having to provide a series of closely spaced locating holes in the rail itself.

A torsion spring 26 is utilized for urging the jaws 1, 1' apart, the spring preferably including a multi-turn helical section 27 retained between the bowl portions 2, 2' of the jaws and a pair of arms 28, 29 at opposite ends of the helical section which extend upward and bear outwardly against the jaws 1, 1'. The upper end 28a of spring arm 28 is bent outwardly at a right angle and is received in a correspondingly positioned aperture 30 in the wall of jaw 1 in order to retain the spring 26 between the jaws. The upper end of spring arm 29 bears against the inner face of jaw 1'. Spring arms 28, 29 lie generally parallel when the jaws 1, 1' are pressed together to the position indicated in Fig. 2 and become spread apart as the jaws open to the position indicated in Fig. 3 The force exerted by the spring arms and which is derived from the helical section is transversely outward and such force increases as the jaws move further apart. This characteristic, which is a desirable one, is inherent in a spring of such construction. More particularly, spring 26 does not act as a straight compression spring but rather as a torsion spring with its center of rotation, i.e. the center of the coil section 27 well below the contact point between the upper end of spring arm 29 and the jaw 1'. It is self-evident from a comparison between the closed jaw position shown in Fig. 2 and the open jaw position shown in Fig. 3, that the contact angle between the upper end of spring arm 29 and the inner face of jaw 1' can vary considerably. A vectorial analysis of the forces at the point of contact between spring arm and jaw will show that practically all of the closing force of the jaws 1, 1' is directed to deflecting the spring when the jaws 1, 1' are completely closed, but when the jaws occupy their most open position, a large percentage of the available force is simply directed through the spring to the center of rotation of the coil section 27 as if the latter were a hinge at the end of a rigid arm and a much smaller component is directed in a direction which would deflect this spring. The force directed into the hinge varies much more drastically than the decreasing'applied force necessary due to the deflection of the spring.

Surrounding the shank portions 4, 4' of the jaws 1, 1' is a collar 32 which is adapted to slide longitudinally of the jaws. Collar 32- is spring loaded in the downward direction by means of a helical spring 33- surrounding the jaws and held in compression between the lower collar and an upper stop constituted by a washer 34 secured to and located below the washer 7, the washer 34 being provided with a comparatively large aperture 35 which constitutes a seat for the upper end of the compression spring 33. Downward motion of collar 32 is limited by contact of the latter with the shouldered portions 3, 3' of the jaws.

A conventional bobbin B, as shown in Fiigs. 1 2. and 3 is provided with a longitudinal bore. The upper end section of the bore has a diameter d and this section is followed by another section having a larger diameter D. The junction of the differently diametered sections d and D establishes a sloping internal shoulder s which as seen in Fig. 3 cooperates with and engages the slopmg external shoulders 3, 3" formed by the heels of the bowl portions 2, 2' of the jaws to hold the bobbin onto the jaws. When a bobbin is to be removed from the position indicated in Fig. 3, a downward pull is applied. This causes the bobbin to move downward and simultaneously press the jaws 1, 1" closer together until they reach the position shown in Figs. 1 and 2 where the bowl portions of the jaws slide against the smaller diametered portion d of the bore. move downwardly, the restoring force built up by compression of spring 36 to the position shown in Fig. 3 pushes the collar 32 downwardly until it is stopped by the jaw shoulders. Due to the confining action of the spring loaded collar 32, the jaws 1, 1' will then remain in this pressed-together position until a new bobbin is pushed over the bowl portions of the jaws and simultaneously raises the retaining collar 32 until the parts reach the position shown in Fig. 3 wherein it is obvious that sufiicient clearance has been developed between the opening through the collar 32 and the slightly tapered shank portion 4, 4 of the jaws 1, 1' to permit the jaws to expand under the action of spring 26 and thus engage the shouldered portion in the bore of the bobbin.

In conclusion it will be understood that the embodiment of the invention which has been described and illustrated is to be considered typical rather than limitative and hence permits of minor structural modifications without, however, departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. In a holder for a bobbin, the combination compris- As the bobbin continues to ing a pair of structurally separate and relatively rigid depending confronting jaws, the upper ends of said jaws being provided with outwardly turned tongue portions and the lower portions of said jaws being provided with external shouldered portions for cooperation with the internal shouldered portion in the bore of a bobbin, means for pivotally connecting together the upper tongued ends of said jaws including a slotted washer in which said outwardly turned tongued portions are received, spring means disposed between said jaws and urging the same apart, a headed bearing pin secured between the upper pivotally interconnected ends of said jaws and extending upwardly and means providing a swivel support for the head of said bearing pin.

2. In a holder for a bobbin, the combination comprise ing a pair of structurally separate and relatively rigid depending confronting jaws, means pivotally connecting said jaws together at their upper ends for movement towards and away from each other, the lower portions of said jaws being bowl-shaped to establish external shouldered portions for cooperation with an internal shouldered portion in the bore of a bobbin, and spring means inserted between said jaws and urging the same apart, said spring means including a multi-tum helical coil section disposed between said bowl-shaped portions of said jaws and a pair of arms extending upwardly from the opposite end of said helical coil section and which bear outwardly respectively against the inner faces of said jaws above said bowl-shaped portions.

References Cited in the file of this patent UNITED STATES PATENTS 1,895,810 Magrath Ian. 31, 1933 2,038,286 Hasbrouck Apr. 21, 1936 2,091,181 Mann Aug. 24, 1937 

